This paper presents a projection-based augmented-reality system (MARVIS) that supports the visualization of internal structures on the surface of a liver phantom. MARVIS is endowed with three key features: tracking of spatial relationship between the phantom and the operator’s head in real time, monoscopic projection of internal liver structures onto the phantom surface for 3D perception without additional head-mounted devices, and phantom internal electronic circuit to assess the accuracy of a syringe guidance system. An initial validation was carried out by 25 medical students (12 males and 13 females; mean age, 23.12 years; SD, 1.27 years) and 3 male surgeons (mean age, 43.66 years; SD, 7.57 years). The validation results show that the ratio of failed syringe insertions was reduced from 50% to 30% by adopting the MARVIS projection. The proposed system suitably enhances a surgeon’s spatial perception of a phantom internal structure.

Augmented reality (AR) delivers virtual information or some of its elements to the real world. This technology, which has been used primarily for entertainment and military applications, has vigorously entered medicine, especially in radiology and surgery, yet has never been used in organ transplantation. AR could be useful in training transplant surgeons, promoting organ donations, graft retrieval and allocation, and microscopic diagnosis of rejection, treatment of complications, and post-transplantation neoplasms. The availability of AR display tools such as Smartphone screens and head-mounted goggles, accessibility of software for automated image segmentation and 3-dimensional reconstruction, and algorithms allowing registration, make augmented reality an attractive tool for surgery including transplantation. The shortage of hospital IT specialists and insufficient investments from medical equipment manufacturers into the development of AR technology remain the most significant obstacles in its broader application.

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This paper introduces a new comprehensive procedure for both geometric and colour calibration of structured light system. In order to perform both geometric and colour calibration procedure, a new calibration artifact is proposed. The intrinsic and extrinsic parameters of projector and camera are estimated by using an extended pinhole camera model with a tangential and radial distortion. Camera image plane coordinates are obtained by extracting features from images of a calibration artifact. Projector image plane coordinates are calculated on the basis of continuous phase maps obtained from a fringe pattern phase reconstruction procedure. In order to stereo calibrate camera-projector system, pairs of corresponding image plane points are calculated with subpixel accuracy. In addition, one of three pattern views is used in colour calibration. RGB values of a colour field pattern detected by camera and their reference values are compared. This comparison leads to derivation of a colour transformation matrix. The performance of the proposed method is tested by measuring plane, sphere and distance reference. Also 360 degrees complex object 3D model from a set of measurements is obtained. Residual mean errors for all tests performed are calculated.